This project is directed towards applying mathematical techniques to experimental methods commonly used for the separation of biochemical species such as electrophoresis or centrifugation. A topic of current interest is the development of a method for decreasing the experimental time used in sedimentation equilibrium experiments. A nonlinear transformation is being investigated but the supression of noise is a major problem. Another phenomenon being investigated is the appearance of double peaks in dynamic isoelectric focussing. We are presently calculating solutions to equations which have the property of producing double peaks due to a nonlinear gradient.